In the wake of last week's blowup with Improbable over the use of the SpatialOS cloud platform in games built on the Unity engine, Unity has once again updated its terms of service, this time to state explicitly that developers are free to use any third-party service they want. CTO Joachim Ante said in a blog post that went up today that developers using Unity own the content of their games and "should have the right to put it wherever you want," and acknowledged that the December 5 TOS update that started the dispute with Improbable "didn't reflect this principle."

"Our TOS update on December 5 was an attempt to define what our terms mean for the cloud and an opportunity to make our business model clearer," Ante wrote. "After listening to developers, we realized how this language came across, and how it would impact your ability to choose."

Section 2.4 of Unity's TOS, "Working with Third Party Service Providers," now states:

Unity developers are free to use any service offered to Unity developers (each, a “Third Party Service”). Unity does not have any obligation to provide support for any Third Party Service provider or Third Party Service under this Agreement. Third Party Service providers may not, without Unity’s express written permission: (1) use a stylized version of any Unity name, trademark, logos, images or product icons, or other Unity-owned graphic symbols; (2) use a product name confusingly similar to a Unity product or that could be construed by Unity developers as being a Unity product or service; or (3) create or use any marketing materials that suggest an affiliation with, or endorsement by, Unity. All use of Unity’s trademarks must comply with Unity’s Trademark Guidelines.

"Some of these [third-party] services will be supported, others will not," Ante explained. "The distinction is that with a supported service, we understand the technology. We make sure the service and Unity work better together for developers. We also ensure that the supported service always runs well on the latest version of our software, so we can help future proof your project in Unity and ensure access to the latest tech."

Unity users will also now be allowed to continue operating under the terms of service of the major (year-based) version of their software, even if the TOS changes in future versions. Terms of service changes will also be hosted on Github, so users will be able to see exactly when and how they change.

Not everyone is fully satisfied with that change, however: One developer said in an AMA that took place earlier today with Ante and Unity CEO John Riccitiello that long-running projects on console platforms will almost certainly be forced to upgrade to a new version of Unity at some point in order to maintain certification, which will effectively force them to accept TOS changes.

"From a technical legal perspective, you make a good point," Riccitiello answered. "Recognizing that we work in a fast changing world with tech and platforms coming, going and morphing, we have to reserve the right to change our TOS in the future if the world changes in ways that make this needed. We had to pick someplace (language-wise) to provide for these possibilities. The key point though is we have no plans to make our TOS more challenging in the future. We are guided by our principles."

Bossa's sandbox MMO Worlds Adrift runs on Improbable's SpatialOS.

Shortly after its dispute with Unity came to light, Improbable entered into a $25 million partnership with Unreal Engine maker Epic Games "to help developers transition to more open engines, services, and ecosystems." And despite the walkback of any restrictions on the use of third-party services in Unity, and the reinstatement of Improbable's licenses, Ante doesn't seem quite ready to forgive and forget just yet.

"We do not consider [Improbable] a partner, and cannot vouch for how their service works with Unity as we have no insight into their technology or how they run their business," he wrote in the blog post. "We know Improbable was in violation even before the December TOS update and misrepresented their affiliation with us. Although SpatialOS is not a supported third-party service, it can continue to be used for development and shipping games."

Riccitiello said basically the same thing in the AMA: "We feel we were right to have terminated their licenses for the TOS violation. We were hoping for an open and honest discussion with them on these issues, but were not able to get to a good discussion. Separately, we heard from our community on our TOS and made changes that reflect the way we feel is right. Aside from Improbable, we’ve never terminated licenses for a service provider, and would not have in this instance had they been more open with us."

As for the specific nature of the dispute, Unity believed that Improbable violated the TOS "both on a technical level and with marketing," Riccitiello said. "We asked them to certify to us in writing that they were not in violation. They did not provide this written certification. They then changed their implementation with a new GDK. We again asked them to certify this was not in violation of our TOS. We asked they do this in writing, and they did not. They also, in our view, used Unity trademarks / brand in their marketing materials and on their website in ways that suggested a partnership, that did not exist."

He said he would not go into further detail about the dispute, however, "out of respect for all involved." I've reached out to Improbable for comment and will update if and when I receive a reply.